(a) Field of the Invention
The present invention relates to a grooved traverse drum for use in a drum winder for winding parallel cheeses or cone cheeses.
(b) Description of the Prior Art
It is known in the art that the grooved traverse drum (hereinafter referred to simply as the drum) is subject to abrasion, though small in amount, at different places in the yarn guide groove, especially at the crossover points, owing to the frequent repetition of friction between the drum and the yarn being wound, said abrasion forming a cause of yarn breaks and hence deterioration in yarn quality.
In an effort to prevent such abrasion, there have been proposed methods which use abrasion-resistant members to be inserted and fixed in the yarn guide groove at the crossover points thereof where the abrasion is particularly severe.
For example, there has been proposed a method wherein an abrasion-resistant member provided on its peripheral surface with a recess which forms a yarn guide groove bottom is inserted and fixed in a traverse drum composed of an outer sleeve of stainless steel and an inner sleeve of porcelain at each crossover point thereof.
According to this method, however, a recess for receiving the abrasion-resistant member must be provided on the boundary between the outer sleeve of stainless steel and the inner sleeve of porcelain and the dimensional accuracy of said recess tends to be so poor as to create a clearance in said boundary. Therefore, careful processing is required in order to reduce said clearance, involving high cost. Further, even if the boundary is filled with an adhesive agent, it will wear out soon, creating a clearance.
I have already proposed a method wherein a cylindrical abrasion-resistant member having a yarn guide groove bottom and side walls is inserted and fixed at each crossover point of the yarn guide groove of a drum made of a single drum constituting material.
According to the above-mentioned method, however, if the yarn guide groove at the crossover points is deep, the boundary portion between the abrasion-resistant member which contacts the yarn and the drum constituting material is remote from the drum surface and located near a narrow groove bottom portion, thus making it difficult to process the groove forming surface of the abrasion-resistant member and the groove forming surface of the drum constituting material in such a manner as to make them flush with each other, thus having a disadvantage that the cost of production of the drum is high,